Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 05d778c2 authored by Charan Teja Reddy's avatar Charan Teja Reddy
Browse files

lowmemorykiller: use oom reaper to free pages of task killed by lmk 



Free the pages parallely for a task that is LMK killed using the
oom_reaper. This freeing of pages will help to give the pages to
buddy system well advance there by we may achieve less number of
killings by LMK.

Change-Id: I5e1ed183437ab243f12cbbf3ae10d9ca5211fc06
Signed-off-by: default avatarCharan Teja Reddy <charante@codeaurora.org>
parent 84a47e8c

drivers/staging/android/lowmemorykiller.c

+17 −0
Original line number Diff line number Diff line
@@ -48,6 +48,7 @@ 
#include <linux/fs.h>

#include <linux/cpuset.h>

#include <linux/vmpressure.h>

#include <linux/freezer.h>



#define CREATE_TRACE_POINTS

#include <trace/events/almk.h>
@@ -116,6 +117,10 @@ module_param_named(enable_adaptive_lmk, enable_adaptive_lmk, int, 0644); 
static int vmpressure_file_min;

module_param_named(vmpressure_file_min, vmpressure_file_min, int, 0644);



/* User knob to enable/disable oom reaping feature */

static int oom_reaper;

module_param_named(oom_reaper, oom_reaper, int, 0644);



enum {

	VMPRESSURE_NO_ADJUST = 0,

	VMPRESSURE_ADJUST_ENCROACH,
@@ -406,6 +411,14 @@ void tune_lmk_param(int *other_free, int *other_file, struct shrink_control *sc) 
	}

}



static void mark_lmk_victim(struct task_struct *tsk)

{

	struct mm_struct *mm = tsk->mm;



	if (!cmpxchg(&tsk->signal->oom_mm, NULL, mm))

		atomic_inc(&tsk->signal->oom_mm->mm_count);

}



static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc)

{

	struct task_struct *tsk;
@@ -524,7 +537,11 @@ static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc) 
		send_sig(SIGKILL, selected, 0);

		if (selected->mm)

			task_set_lmk_waiting(selected);

		if (oom_reaper)

			mark_lmk_victim(selected);

		task_unlock(selected);

		if (oom_reaper)

			wake_oom_reaper(selected);

		trace_lowmemory_kill(selected, cache_size, cache_limit, free);

		lowmem_print(1, "Killing '%s' (%d) (tgid %d), adj %hd,\n"

			"to free %ldkB on behalf of '%s' (%d) because\n"

include/linux/oom.h

+2 −0
Original line number Diff line number Diff line
@@ -82,6 +82,8 @@ extern struct task_struct *find_lock_task_mm(struct task_struct *p); 
extern void dump_tasks(struct mem_cgroup *memcg,

		const nodemask_t *nodemask);



extern void wake_oom_reaper(struct task_struct *tsk);



/* sysctls */

extern int sysctl_oom_dump_tasks;

extern int sysctl_oom_kill_allocating_task;

mm/oom_kill.c

+8 −3
Original line number Diff line number Diff line
@@ -608,18 +608,23 @@ static int oom_reaper(void *unused) 
	return 0;

}



static void wake_oom_reaper(struct task_struct *tsk)

void wake_oom_reaper(struct task_struct *tsk)

{

	if (!oom_reaper_th)

		return;



	/* move the lock here to avoid scenario of queuing

	 * the same task by both OOM killer and LMK.

	 */

	spin_lock(&oom_reaper_lock);

	/* tsk is already queued? */

	if (tsk == oom_reaper_list || tsk->oom_reaper_list)

	if (tsk == oom_reaper_list || tsk->oom_reaper_list) {

		spin_unlock(&oom_reaper_lock);

		return;

	}



	get_task_struct(tsk);



	spin_lock(&oom_reaper_lock);

	tsk->oom_reaper_list = oom_reaper_list;

	oom_reaper_list = tsk;

	spin_unlock(&oom_reaper_lock);